141 



verns, we find all the characters of a chemical 

 precipitate. The carbonat of lime has not been 

 held in suspension ; it has been actually dis- 

 solved. I am aware, that, in the experiments 

 of our laboratories, this substance appears solu- 

 ble only in water strongly impregnated with 

 carbonic acid : but the phenomena, which na- 

 ture daily presents in caverns and springs, are 

 sufficient proofs, that a small quantity of car- 

 bonic acid is sufficient to give water, after long 

 contact, the power of dissolving some portion of 

 carbonat of lime. 



As we approach those periods, in which orga- 

 nic life displays itself in a greater number of 

 forms, the phenomenon of grottoes becomes 

 more frequent. There exist several under the 

 name of baumen*, not in the ancient sand- 

 stone, to which the great coal formation belongs, 

 but in the Alpine limestone, and in the Jura 

 limestone, which is often only the superiour 

 part of the Alpine formation. The Jura lime- 

 stone so abounds with caverns-f- in both conti- 



* In the dialect of the German Swiss, Balmen. The 

 Baumen of the Sentis, of the Mole, and of the Beatenberg, 

 on the borders of the lake of Thun, belong to the Alpine 

 limestone. 



+ I shall mention only the grottoes of Boudry, Motiers- 

 Travers, and Valorbe, in the Jura j the grotto of Balme 

 near Geneva ; the caverns between Muggendorf and Gailen- 

 ruth in Franconia ; Sowia Jama, Ogrodzimiec, and Wlodo- 

 wice, in Poland 



